ARM: dts: stm32: Add timer interrupts on stm32mp15

The timer units in the stm32mp15x CPUs have interrupts, depending on the
timer flavour either one "global" or four dedicated ones. Add the irqs
to the timer units on stm32mp15x.

Sync the DT Files with linux kernel v6.1 and with commit a9b70102253ce
("ARM: dts: stm32: Add timer interrupts on stm32mp15")

Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>